Cool Earth Solar's Cool-Headed Approach to Saving the World

Last year we covered Cool Earth Solar's snagging of $21 million in venture funding for its solar concentrating balloon project. CEO Rob Lamkin was at Clean Tech Forum this week and we spoke with him about how they came up with this seemingly odd idea. Turns out, its a big-picture model that we admire, and that other start-ups may want to consider before setting out on new projects. Lamkin was excited to share the story about how the solar balloon concept was devised because he feels that it shows the best way, and best reason, for coming up with a particular product.

Cool Earth Solar Getting Started on an IdeaThe team didn't want to just take a product that's already out and improve it or tweak it and try to make a lot of money by going just one step further. Instead, they wanted to solve a major problem shared by everyone on earth. They focused the majority of their brainstorming time coming up with how to define the problem. They wondered, is it green house gases? Is it energy security? Is it electricity demand? Looking at overarching problems and figuring out what is really needed helped them to develop the technology.

The Two Most Abundant ResourcesThrough research, the team discovered two things. Solar is the only resource abundant enough to address all the issues the team considered to be the biggest problems. To harvest enough solar, the team figured out that we would need 100 miles by 100 miles of the earth's surface covered in solar collection technology to power the entire world on clean renewable energy. Delving into more research, they found that the only material we make in enough abunance to cover this kind of area affordably is thin film plastic.

Playing with PlasticSo, the team went with that material. They tried different shapes, different layouts, and finally came up with the best shap - an air inflated balloon 8 feet across. Half of the balloon is clear, half is coated in aluminum. The sunlight comes through the clear material, bounces off the aluminum and at the focal point, PV material is used to collect the 400x concentrated light.

Ultimately, a balloon is about two pounds of plastic that costs about $2. And ultimately, Lamkin says, this is a materials problem. No other material used in solar power generation can be found so cheaply - not mirrors, not metals. But...it's plastic.

But....It's Plastic (?)Lamkin argues that plastic isn't bad, but what we do with it can be. He points out the Great Pacific Garbage patch as a major example of how we've done wrong by plastic. He says, however, when you use plastic for something like solar power, the pros outweigh the cons. He also notes that manufacturers of thin film plastic can use recycled plastic. While he's not sure right now if Cool Earth Solar can know if they're purchasing thin film made from recycled plastic, he assured me he was going to look into it.

Maintaining the Bigger PictureThe team keeps that big picture goal in mind as they form the company and the product - they constantly remember that they're trying to efficiently and cost effectively solve a global problem of renewable power generation. Their product has been 100% shaped by their desire to see the world off of fossil fuels, minimizing our carbon footprints, and being powered by our most abundant resource by using our most abundant materials.

Regardless of the pros and cons of the solar concentrator balloon, the bigger point here is that the company and its team aren't out to just put another product on the green market to try and make a buck. It is this outlook that other companies should (and many do) maintain if we're going to solve the crises at hand.

Cool Earth Solar currently has prototypes in Livermore, California collecting data, and they hope that by mid-year 2009, they'll build their first commercial power plant somewhere in central California on pre-disturbed land such as fallow farm land.